The rail brakes or car retarders are essentially used in railroad sorting or classifying to slow down or brake the carriages or vehicles of incoming trains which are isolated and cut into individual or sections of several carriages or cars which are directed toward and are moved over and down the hump of a classification or marshalling yard.
In some well-known track braking apparatus of this type, the air operating cylinders are mounted so that their axes are horizontal with respect to ground level. As a result, the dimensions of these previously known track brakes are generally very large, since the horizontal stroke of the pistons within the cylinders has to be taken into account in order to determine the space transversely occupied by the equipment.
On the other hand, it is also known to provide and equip tracks of sorting or class yards and the like with railway braking apparatus whose cylinders are arranged in one or a single line alongside the track rail. In this case, the gripping or pinching action on the sides of the wheel is brought about by having the single line of cylinders simultaneously operate both of the frictional bars which are located on opposite sides of the running rail. In this latter type of track brake, the operation of the braking bar which is located on the other side of the rail from pistons and cylinders, makes it necessary to arrange for disposition of the movable levers underneath the rail which is both expensive and cumbersome.
The subject invention eliminates the above-mentioned disadvantages and one object being in particular to provide track braking apparatus for railway vehicles which is not very expensive, takes up less space in the transverse direction and is very easy to assemble and disassemble while having a great rigidity and modular form.
For this purpose, the track braking apparatus is especially adapted for railroad vehicles and involves a car retarder which comprises at least one frictional braking beam situated parallel to a track running rail and supported on sleepers or crossties. The braking or retarding apparatus includes at least one elastic actuator or power operator, such as, a compressed-fluid and/or spring assisted cylinder one end of which, namely, either chamber body or piston rod, is capable of pushing through the intermediary of a mechanical transmission member (directly in the case of tightening by the actuator or indirectly in the case of tightening by the wheel pressure) the frictional braking beam against at least one wheel of a vehicle moving over the track rail. The apparatus is characterized in that the mechanical transmission member is a brake lever located in a median plane above the upper part of the sleepers at a small distance therefrom. The fulcrum point line of rest of the lever is linked to a support which is disposed on at least two adjacent sleepers or crossties and which is at least transversely attached thereto. In between the crossties, there is lodged or located the compressed fluid cylindrical operator or actuator whose other end, namely, the end opposite to that which is linked to the brake lever, is pivotally jointed to a reaction support or holder which is also fixed to at least the two adjacent sleepers or ties in such a manner so as to lodge or locate the cylindrical operator below the upper part of the lever and between the sleepers or ties. Thus, the crossties absorb the longitudinal and transverse reactions that the wheels transmit to the frictional braking beams. The axis of the brake cylinder and, in turn, the axis of expansion of the flexible operator or actuator is substantially perpendicular to the line or, respectively, to the plane which meets the fulcrum point or line of rest of the brake lever at the point, line or spot of connection of the cylinder or actuator with the brake lever. This tends to reduce to a minimum the strain and stress applied to the friction beam and, in turn, the force that is transmitted by the brake cylinder to its reaction support and to the lever.
The reaction support for the cylinder or operator is disposed at the lower part between the two adjacent sleepers or crossties.